The Law of Conservation of Mass

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What is the Law of Conservation of Mass?

Back

The Law of Conservation of Mass states that in a closed system, the total mass of the reactants before a chemical reaction is equal to the total mass of the products after the reaction.

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What is a Coefficient in a chemical equation?

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A coefficient is a number placed in front of a compound or element in a chemical equation that indicates how many molecules or atoms are involved in the reaction.

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What is a Subscript in a chemical formula?

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A subscript is a number written below and to the right of a chemical symbol that indicates the number of atoms of that element in a molecule.

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What happens to the mass of substances during a chemical reaction?

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The total mass of the substances remains the same before and after a chemical reaction.

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If 200 g of water is frozen, what will be the mass of the frozen water?

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The mass of the frozen water will be 200 g.

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What is the difference between a reactant and a product?

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Reactants are the starting substances in a chemical reaction, while products are the substances formed as a result of the reaction.

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How can you determine the number of atoms in a molecule?

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You can determine the number of atoms in a molecule by adding the subscripts of each element in the chemical formula.

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What is the significance of balancing a chemical equation?

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Balancing a chemical equation ensures that the Law of Conservation of Mass is upheld, meaning the number of atoms for each element is the same on both sides of the equation.

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What does it mean if a chemical equation is unbalanced?

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An unbalanced chemical equation does not have the same number of atoms of each element on both sides, violating the Law of Conservation of Mass.

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What is an example of a chemical reaction that demonstrates the Law of Conservation of Mass?

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The reaction of hydrogen and oxygen to form water: 2H2 + O2 → 2H2O, where the total mass of reactants equals the total mass of products.